James l



J. L. WITHBY. Machine for Sewing Boots and Shoes.

No. 224,063. 'Patented Feb. 3,1880.

I'iEA.

UNITED STATES PATENT riicE.

JAMES L. WITHEY, OF MELROSE, ASSIGNOR TO GORDON MGKAY, TRUSTEE` FOR MOKAY SEWING MACHINE ASSOCIATION, OF BOSTON, MASS.`

MACHINE FOR SEWING BOOTS AND SHOES.

SPEGIFICATION forming part of Letters Patent No. 224,063, dated February S, 1880. h h

' Application ledMarch 26,1879. i

To all whom t may concern:

Be it known that 'I, JAMEs L. WITHEY, of Melrose, county of Middlesex, State of Massa- `chusetts, have invented an Improvement in Machines for Sewing Boots and Shoes, of

which` the following desription, in connection with the accompanying drawings, is a specification.

This invention relates to improvements in Io sewing-machines for boot and shoe work where a waxed thread is employed.

My improvement is shown as embodied in connection with` the horn of the so-called McKay machine!7 h Waxed thread in the McKay sole-sewing machines is commonly held upon a large tin spool, it and the thread, when fully wound,

weighing about two and one-half pounds.

Itis a great desideratum, in uniting soles 2o to `uppers by a waxed thread, that the leather be drawn together as iirmly as possible, in

order to -prevent the plates or portions of leather united, by the stitches from slipping one upon the other, such movement cutting the thread and causing what is commonly called ripping.7 The waxed thread in sewing is consequently subjected to all the strain it will bear without breaking.

The large spool of waxed thread commonly used has a nut and washer, by which to adjust the tension of the thread to all it will stand. h

In this class of sewingmachine the motion of the hooked needle as it commences to rise is much slower than at the central portion of its upward stroke. The force exerted upon the thread by the hook of the ascending needle, provided the `thread extending from the h whirl or work to the spool is stretched taut,

4o must be sufficient to rotate the spool or start it from a position of rest.

In the McKay machine the powerful tension or strain under which the thread is held durt ing the time the machine is sewingis determined by the adjustment of friction devices connected with the spool, and the hook of the needle during sewing, by its action on the thread, turns the heavy spool wit-h a jerk, turns it too far, as the momentum of the spool is very considerable, and the needle then 5o draws on a loose loop, and as the slack formed by the momentum ot` the spool is consumed the hook of the needle again jerks the thread and again turns the spool. These jerks to overcome the inert-ia of the spool and the slack 5 5 caused by its momentum seriously impede the `operation of the machine, reduce its speed.

strain the needle, break the thread, and limit the speed at which the machine maybe run and do good work.

The aim of this invention is to provide the horn with a stationary wound cop of sole-fastening waxed thread so wound thereon that the thread ldrawn up by the hooked needle when rising will berelieved from the variation of tension due to inertia and momentum ofthe usual rotating spool of thread. I employ with the said thread ay tension device to act uniformly upon the thread, thereby subjecting it to equal and uniform tension dur- 7o in g the formation of each stitch, whichV insures a stronger seam;

In the McKay machine, wherein the thread is held upon a spool, as described, the maximum speed ot' the machine without breaking 75 the thread too much to do good work is about two hundred and fifty stitches per minute.

In this myimproved plan, wherein the waxed thread is wound in conical layers to form a cop, from which the thread may be drawn 8o without rotating the cop, it is possible to run such machines practically at the rate ot' about six hundred and fifty stitches per minute, and do better work with less breakage of thread than in the old plan at the rate of two hundred and iifty stitches per ininute.

The-wax upon the wound thread, prefera`V bly like that used in hand-work, acts to hold the rounds or layers of thread together, so that such layers reel oifo'nl y as drawn off posi- 9o tively.

I have also provided a novel tension device or wheel, which acts uniformly upon the thread and which is so constructed as to permit the surplus wax left on it to escape through several small outlets therein, which prevent all liability of the wax becoming filled or baked intp the sharp V ot' the said wheel, which is kept hot by the usual lamp,

empece gas, or steanrjet wax of the thread Figure 1 represents,v in side elevation, a revolvin g horn provided with my invention and placed in operative position with relation to the usual hooked needle, such as is well known in the McKay machine. Fi ofthe base of the horn and g. 2 is a top view the attached tension devices and thread-cop, the upper part of the horn being in section; Fig. 3, a longitudinal section taken through the tension device or wheel, and Fig. 4 an enlarged vertical and cross section ofthe wheel alone.

The revolving` horn a will rotated as usual, and will containl the usual* be supported and whirl, whirlactuating shafts, `and heating mechanism now commonly employed in the well-known McKay machine, and the hooked needle b will be actuated as The waxed thread c, to b in that machine. e drawn into the soles and uppers to be united, instead of being held upon the usual headed reel turning about a vertical pivot at the ofthe horn, as in the present McKay is placed on a bobbin, d, ixed upon center of rotation machine, an arm or bracket, e, attached to the horn, the said bobbin not rotating axially.

The waxed thread is carried from the horizontally-placed bobbin d through a guide-eye,'f, and thence under and partially about the tension-wheel g, and thence upward along within the horn and through the eye in the usual whirl, from which it is taken by the hooked needle b. This tension-wheel g is shown as composed of a single piece of metal groo as to form a sharp V-shaped recess or in which the thread is wedg ciently` hard to prevent the without also rotating the wh ved annularly, so space, ed or drawn stifli- .thread moving eel.

The force required to rotate the wheel, and

consequently the forcewith which the thread is held, and which has to be overcome by the pull of the needle on the thread means of tension-controlling as a nut, h,and a spring, L) on the rod y', that serves as wheelg, the said rod j being is regulated by devices, (shown which are placed the axis for the squared or otherwise shaped, as at 2, to prevent it from rotating, yet permitting it to be rection of its lengthto release the w permit it to rotate freely wh moved in the diheel g, and en required.

This longitudinal movement of the spindle or rod j and devices ,as shown in the drayvin gs,

to so move it are not herein claimed by me, as they will form the subject-mat ter ofanother application for patent made The gas-j et by another party.

or other usual heating means (not herein shown) will warm the wheel g sufficiently to keep soft the to the said wheel from th and consequently the usual it, necessitated a constant ch wax which adheres e commencement to the completion of the unwi nding operation, difficulties expeng headed spool, as u n wound from an ge of tensio to compensate for the decreasing diameter of the mass of thread on the spool and its weight, are avoided. permitting the thread toibe subjected in a uniform manner to all the tension it will bear without breakin B'y employing a bobbin of the kind described and shown to hold the waxed-thread of a sole-sewing machine, instead of the usual rotating headed spool, the speed of the machine is greatly increased. It is made to perform better work with the same material, less attention is required on the part of the operator, and time heretofore wasted by stopping to mend broken threads is saved.

The tension of the thread is possible to draw the stitches uniformly taut. The bobbin upon which the waxed thread which the thread is unwound, and is and may be shaped as any ordinary lling-bobbin.

The essential feature of the waxed-threadholding bobbin in this my invention is, that it shall be so shaped, held, and placed. that the waxed thread may be easily drawn thereof strain to draw off the waxed thread being unaffected by size or weight of the bobbin or the fact that it is more or less fully wound.

By reason of the shape of the base of the bobbin the waxed thread may be wound as is the filling in shuttles, waxed thread so wound unwinding easier than if wound in any other shape.

The axis of the bobbin is substantially in line with the guide-eye j", next to the tensionwheel g, and the thread therefore unwinds evenly from the bobbin. This waxed cop or bobbin of thread, located as described with relation to the horn and wound on a stationary bobbin, enables the` thread to be more uniformly delivered than would be the ease were a ball of dry thread used, the thread from the ball passing through a waxing apparatus. Dry thread cannot be thoroughly and practically waxed on the horn on its way to the usual whirl and needle. l

It will be observed in this my invention that the action of the tension device upon the waxed thread is constant, and that the thread is not released from tension as the needle forms the loop.

I desire it to be understood that Iv do not broadly claim. supporting' the needle-thread spool upon a nearly-horizontal pin to obviate rotating the said spool, and I am aware that shuttles have had their thread wound on bobbins like the bobbin employed by me.

1. The tension-wheel provided with the V- shaped peripherical groove and with transverse outlets for the wax, the said outlets intersecting the bottom ofthe said groove, substantially as and for the purpose described.

2. The rotating horn and the tension dei vlce provided with the V-shaped peripherical groove and intersecting passages or outlets,

being uniform, it A is wound is without a head at that end from from without rotating the bobbin, the amount l IOO IOS

IIO

as described, for the Wax at the bottom of the In testimony whereof I have signed my 11a-me seid groove, combi-ned with a bracket or bobto this speciiioation in the presence of two sub- 1o bin-holder adapted to support a lling-wound soribing Witnesses. cop or bobbin of waxed thread, to permit the 1 thread to be taken off at a uniform tension JAMES L' WIFlHEY by the hooked needle for the formation of Witnesses:

each stitch without rotating the said cop or Gr. W. GREGORY,

bobbin. N. E. WHITNEY. 

